If I remember correctly, this NPE doesn't come alone but you have to go into that tasks' log to find the rest as the job output you have only shows what ended up killing the task. Go to the jobtracker's web ui, click on your job, click on the number of failed tasks, look at the log of one of those tasks, and look for anything that looks bad at the end of the log before the NPE.
Hope this helps, J-D On Mon, Nov 14, 2011 at 3:30 PM, Royston Sellman <[email protected]> wrote: > Apologies if this is the wrong forum, or has come up before, or is > RTFM-class... > > I'm trying to run HBase example code. I think I have HBase running OK on my 6 > node cluster: I can create tables with the HBase shell. I can create tables > with the ExampleClient from Chapter 13 of the Hadoop book. I can load the > HBase Master: namenode:60000 web page and see tables I've created. But when I > try to run SampleUploader from the HBase examples I get the (not very helpful > to me) exception below. I get a similar error when trying to run the > HBseTemperatureImporter bulk load example from the Hadoop book also i.e. > mapred.JobClient failing 4 times before giving up. > > Thanks, > Royston.
